Presentation on theme: "Memory Section 7.2. Types of Memories Definitions – Write: store new information into memory – Read: transfer stored information out of memory Random-Access."— Presentation transcript:
Types of Memories Definitions – Write: store new information into memory – Read: transfer stored information out of memory Random-Access Memory (RAM) – Can read and write Read-Only-Memory (ROM) – Read only
Interesting Facts Interesting fact of RAM: the time it takes to transfer information to or from any desired random location is always the same A word =a group of bits – A group of 8 bits is called a byte. –
Two Types of RAM Static RAM (SRAM): Stored information remains valid as long as power is applied to the unit. Dynamic RAM (DRAM): Stores binary information in the form of electric charges on capacitor provided inside the chip by MOS transistors.
Switching Time Waveforms 17 nS23 nS -7 nS for address -14 nS for data A negative hold time means that the address/data can change before the rising edge of WE because the there is internal delay through the chip.